The present invention generally relates to a system for forming images, such as laser printers, copiers and facsimiles, and in particular to a recording signal generating circuit for printing in which a recording signal corresponding to image information is generated, which is provided in an electrostatic recording part of an image forming system.
In conventional image forming systems such as laser printers, copiers, and facsimiles, it is well known that an electrostatic latent image is formed by projecting a laser beam onto a photosensitive substance which is precharged in a main scanning direction and that toner is deposited and then fixed on the formed electrostatic latent image to thereby obtain a recording image in the form of a hard copy of information optically scanned.
In a case where a so-called negative/positive development is employed in such conventional image forming systems, it is very difficult to clearly reproduce an isolated one-pixel point, an isolated line having a one-pixel width and consecutive pairs of black and white lines each having a one-pixel width. In other words, the reproduced images are light, compared with a portion in which a plurality of pixels are successively printed on a sheet of transfer paper in the main scanning direction. This disadvantage arises from properties of the photosensitive substance and developing substance used.